<span>sin x = (кор из 3) / 2</span>
<span>x = 60 градусов</span>
3,7,11,15,19,23,27,31,35 и т . д .
Cos^2(pi/12)+sin^2(pi/12) = <span>cos^2(pi/12)+(1 - cos^2(pi/12) ) =
= (</span>cos^2(pi/12) - cos^2(pi/12) ) +1 = 0 + 1 = 1
Ответ*&/$#@$/$##^///////////////